@Andreas Just: now, what about a guide server?

That sounds interesting! 🙂 Are you perhaps referring to HyperBrowser from the AmigaGuide V39 developer examples? As far as I know, it used Dynamic Node Hosts to browse live system structures. I've been looking into amigaguide.library and amigaguide.datatype recently, and the missing host API is already on my list of AROS gaps. Was HyperBrowser the application you had in mind?